22 points
The steam survey doesn’t count individual games; the Steam client itself collects and sends the data after prompting the user for permission. So all the matters is the OS visible to the Steam Client.
3 points
Which is, in that case, Windows 10 in a Wine bottle.
Steam.app can’t run Windows games directly on macOS, like it does on Linux with Proton. So you have to install the Windows version of Steam in a Wine bottle to be able to install and run Windows games from Steam on macOS
